Comparison of diamond growth with different gas mixtures in microwave plasma asssited chemical vapor deposition (MWCVD)

AUTOR(ES)

Corat, Evaldo J., Ferreira, Neidenei G., Leite, Nélia F., Trava-Airoldi, Vladimir J.

FONTE

Materials Research

DATA DE PUBLICAÇÃO

2003-01

RESUMO

In this work we study the influence of oxygen addition to several halocarbon-hydrogen gas systems. Diamond growth have been performed in a high power density MWCVD reactor built in our laboratory. The growth experiments are monitored by argon actinometry as a reference to plasma temperature and atomic hydrogen production, and by mass spectrometry to compare the exhaust gas composition. Atomic hydrogen actinometry revealed that the halogen presence in the gas phase is responsible for a considerable increase of atomic hydrogen concentration in the gas phase. Mass spectrometry shows similar results for all gas mixtures tested. Growth studies with oxygen addition to CF4/H2, CCl4/H2, CCl2F2/H2 and CH3Cl/H2 reveals that oxygen increases the carbon solubility in the gas phase but no better diamond growth conditions were found. Halogens are not, per se, eligible for diamond growth. All the possible advantages, as the higher production of atomic hydrogen, have been suppressed by the low carbon solubility in the gas phase, even when oxygen is added. The diamond growth with small amount of CF4 added to CH4/H2 mixture is not aggressive to the apparatus but brings several advantages to the process.

Documentos Relacionados

• Very high growth rate chemical vapor deposition of single-crystal diamond
• Different carbon nanostructured materials obtained in catalytic chemical vapor deposition
• Metallurgical response of an AISI 4140 steel to different plasma nitriding gas mixtures
• Support effect on carbon nanotube growth by methane chemical vapor deposition on cobalt catalysts
• Carbon nanotube atomic force microscopy tips: Direct growth by chemical vapor deposition and application to high-resolution imaging